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Wood fibre sheathing

When I visited a collective of Tiny House builders earlier this year, they recommended that I sheathe my structure with wood fibre boards. Though they are made from pressed wood fibre, they have a different texture than OSB or MDF. They are lighter, 'fluffier' perhaps. And according to the manufacturer's website they are entirely compostable- no chemical glue. They provide extra insulation, regulate humidity, and are wind and rain-tight. They have a tongue-and-groove structure that interlocks the panels- although my surfaces are so small that I couldn't really take advantage of that!




One big question which I hadn't resolved in the design was how to make these panels go around the curved part of the structure. I ended up making saw cuts to half the depth of the panel and then bending them. It worked, although I think that compromised the wind-and-rain tightness...
To fill in the gaps, I mixed the leftover fibre with water and glue and used that as a paste. It's…

BAAAtts

I knew I wanted to insulate the Carabane with sheep's wool. It is non-toxic, renewable, has good thermal and acoustic insulation properties, and it regulates humidity. One website quipped 'Wool is terrific insulation: ask any sheep.' It makes me think of the sheep I saw in Iceland in October- the snow on their backs didn't even melt because none of their body heat was escaping! And as we know from merino clothes, it is warm and it breathes. This is just as important for walls and roofs as it is for shirts. If the humidity in the air is above 65%, wool will absorb moisture, and if it is below, it will release it. Moisture control is a key issue in construction (interiors tend to be hot and damp while exteriors cold and dry, resulting in the migration of moisture through walls and roofs). So the key is finding materials that allow for the free movement of this vapour, in order to prevent mold and mildew building up inside the walls.

After searching for a while I found …

Barn Raising

The trailer base was delivered to my workshop on Friday. It is made in the Netherlands but the importer is based in France. This is the part of the caravan that fulfills all the legal requirements for transport on the road: brakes, lights, etc. The permitted total weight is 3.5 tonnes and the weight of the trailer itself is 570kg. That means that my construction can’t weigh more than 2.9 tonnes. But it won’t. I’ve calculated the weight at around 1.8 tonnes. And the importer said that most tiny houses that are 6m long won’t go over the weight limit- even if they have two mezzanines.



So I had the trailer, and I had the walls. Now, to put them together…

I invited my friends for an old-fashioned 'barn raising' party. I provide music, tea, and snacks, they provide the extra arms! We lifted the walls onto the trailer and put up the roof beams. I had pre-installed joist hangers on both walls to support the beams.




Now it's starting to look like the model! That's always a momen…

Plywood edges

I knew I wanted the interior of the caravan to be finished in plywood- it's easy to work with, relatively cheap, adds shear strength to the wood structure, and looks nice (at least in my opinion). But with plywood, there is always the question of how to treat the edges, which have a very different aesthetic than the surface. A lot of tutorials online say to glue a strip of veneer onto the edge so that it "looks like real wood". But my philosophy has always been that materials should look like themselves and not try to be something else. So I did some tests with my router. I had learned from my shelf project that a simple bevel on the edge of a panel gives it a finished look. Bevelling the edge will also help smooth off any splinters that might be left over from the saw cut. I tried one with a 45° bevel and one with a rounded corner, which I felt might be softer to the touch. I prefer the angled bevel though- it looks cleaner.




Shoulder studs

The vertical framing studs need to hold up the double beam as well as hold it together. So in each stud I'm cutting out 'shoulders' that allow the beam to rest. The 'head' of the stud will be between the two beams, screwed into place.

My Japanese saw works well for cross-cuts (against the grain), but it is very tiring to make rip cuts (with the grain). So I think I'm going to build a jig for the circular saw.


Double beams

For insulation and structural purposes, I wanted the wood structure to be 10cm thick in the walls and 12cm thick in the roof. But that means where the wall attaches to the roof, there is a corner with a surface of 10x12cm. Having a beam with a cross-section of 10x12cm would be overkill, and it would add extra weight that I don’t need. Plus, I have sections of the beam that need to be curved, and it would be very hard to curve a piece of wood that big. Therefore, I’ve decided to build a double beam made of two sections of 2.7x12cm, and put 5cm of insulation between the two sections, for a total thickness of 10cm. The curved parts I had cut out of 3-ply spruce by a CNC router. My first task for the caravan is to assemble these beams.

I’m using my router to make an overlapping joint of 5cm between the curved and straight pieces.


Shelved 2

My friends commissioned me to build storage under the open staircase in their apartment. I wanted to keep the open feeling of the staircase, so not completely build it up. And I also wanted to respect their quirky, eclectic decor and taste for natural materials. I chose a system of boxes + planks. This also made the construction process easier, as I was able to assemble the boxes separately at my apartment.

For a combination of workability+price, I decided to use 3-ply spruce to construct the boxes. As the name implies, there are 3 layers of wood glued perpendicular to each other. To make clean joints, I really wanted to make the three layers wrap around the corners. So I devised a system of routering that stepped the corners according to the thickness of the plys.


Of course, this kind of joinery would not have been feasible without a router. This was the first project where I used my new handheld router. I really liked the clean edges it gave. It was useful for everything from maki…